Pruritus circumscriptus sine materia: a sequel of postzosteric neuralgia. Evaluation by quantitative psychophysical examination and laser-evoked potentials.

A case of circumscribed pruritus existing since 1 year on clinically uninvolved skin is reported, in which careful history revealed a 5-year previous episode of herpes zoster in the same dermatome. Impairment of cutaneous sensitivity was evaluated by use of a quantitative psychophysical examination and laser-evoked cortical potentials (LEP).